Indomethecin has been reported to prevent the side effects observed in patients receiving recombinant alpha interferon. Nothing is known about the potential of this drug to also inhibit or possibly augment the antitumor effect of this drug. In this study with a disease known to be responsive to alpha interferon, malignant melanoma will be treated with moderately high doses of recombinant alpha interferon. It will be randomized to receive in addition either no other therapy or indomethecin at a dose of 25 milligrams given three times per day. Hematologic monitoring is carried out during the course of this therapy to determine if indomethecin will have any effect upon interferon mediated biological responses. In addition, acute and chronic toxicities will be monitored to determine if indomethecin can reduce these side effects. So far 33 patients have been entered on this trial. There has been one complete response, one partial response, 14 patients have had stable disease, 13 patients had progressive disease and were removed from the study, and four patients were removed from the study because of progressive toxicity not remedied by interferon dose reduction. Indomethecin did appear to be effective in preventing some of the side effects associated with interferon. Seven of 17 patients receiving no indomethecin had chills whereas only 1 of 16 receiving indomethecin had chills. Fevers occurred in 7 of 16 patients receiving indomethecin and 14 of 17 not receiving indomethecin. Fatigue, however, occurred in 7 of 16 patients receiving indomethecin and 4 of 17 not receiving indomethecin. Nausea and vomiting occurred in 4 patients receiving indomethecin and 6 not receiving indomethecin. Weight loss exceeding 10 percent of the patient's body weight occurred in one patient receiving indomethecin and one not receiving indomethecin. Thus, it appears that antitumor effectiveness of interferon is not reduced by concurrent administration of indomethecin but that toxicity is reduced somewhat. Unfortunately, the low response rate in this study will make it difficult to conclude that interferon does not interfer with the therapeutic acitivity of interferon.